Unloading mechanism



Aug. 11, 1925.

J. l. POLLOCK UNLOADING MECHANISM ori inal Filed May 25, 1921 3Sheets-Sheet l labour- Aug. 11, 1925. 1,549,149

J. l. F'QLLOCK UNLOADING MECHANI SM Original .Filed May 25. 1921 3Sheets-Sheet 2 ATTORNEY Fatented ll, i925.

UMTEn s1" isaaia UNLOA D-ING- Application filed May 25, 1921, Serial No.472,346.

To all whom it may concern:

Be it known that 1, JAMES I. POLLOOK, a citizen of the United States,residing at Seattle, in the county of King and State of ashington, haveinvented a certain Unloading Mechanism, of which the follow- .ing is aspecification.

My invention relates to the art of unloading devices. More particularly,it relates to devices for unloading lumber or the like from trucks ordollies which are used in transporting the lumber about the premisesduring the operation of manufacture.

In general, I provide a tilting platform capable of supporting a load oflumber; a

discharging frame mounted upon said platform adapted to move againstsaid load of lumber so that it may be pushed off the 'dollies tier bytier; a clamping arm arranged to hold the said load in position whilebeing tilted; and driving mechanism to actuate said parts in theirvarious operations.

After the lumber is prepared for drying in the kiln, the practice is tostack it upon trucks, such stacking being done after a definite 'manner,namely, the boards are placed on edge with spacing strips there-:between. Mechanism for effecting the unloading of such trucks ordollies as heretobefore designed, operates by causing the lumber to belifted and then discharged upon carrying belts or other receivingmechanism. Such unloading mechanism has lugs positioned at intervals,which ordinarily represent the height of a tier of lumber on such drykiln truck. In the event that there is a slipping back of the boards, itis manifest that it will take a lug to lift each board that so fallsback and hence the capacity and efliciency of the machine is very'muchreduced. Such slipping back is common in view of the fact that theboards, after being withdrawn from thedry kiln, are usually warped andof irregular shape so that such lugs are very apt to engage one end onlyof a tier and wreck the same by causing one end to be elevated while theother end is not similarly acted upon by the corresponding lug, owing tothe warped condition of the lumber.

Furthermore, such unloading mechanism as now obtains in common practiceis objec- .tionable by reason of the percentage of broken or marredboards which result.

MECHANISM.

Renewed January 112, 1925.

Since such mechanism operates by lifting the boards upward,comparatively complex machinery for such lifting is involved. Themanifest lack of efficiency .of such machines by reason of such actiongreatly augments the labor cost element, which is of especial importancein the manufacture "of lumber, since in sections of the country wheresuch manufacture is commonly carried on, there is at all times ascarcity of labor, "or such labor is only available at high prices.

One condition to be met in'unloading is that the stack must be supportedso that it will not fall to pieces when the bolster stakes are removed,and yet the boards of the stack must be free to fall out of the stacksuccessively in a predetermined, orderly manner. Also, the stack must benecessarily broken by removing a tier of lumber at a time, since thespacing strips subdivide the stack into tiers. And still anothercondition is that the act of unloading must be so performed that theboards are delivered in a suitable manner for further handling, and suchunloading, in providing an efficient machine, should be limited only bythe speed of the sorting table. Such mechanism must be subject tocontrol throughout its operation and simple in construction. Finally,the vertically positioned spacing strips which divide the lumber intotiers must be disposed of in a manner which will not interfere with ordelay the movements of the lumber.

The object of my invention in general -1s to provide a device which willovercome the above objections and meet the said conditions. A primaryobject of my invention is to provide an unloading mechanismcharacterized by its simplicity, efiiciency and economical use of powerin its operation. Another primary object of my invention is to providean unloading mechanism for lumber or the like which will remove the samefrom the stack on a truck or other transporting means, tier by tier.Another primary object of my invention is to provide such an unloadingmechanism which will maintain the stack and yet permit of the dischargeof the boards successively, tier by tier, at a predetermined rate.

The above mentioned general object of my invention, together with othersinherent in the same, are attained by the mechanism illustrated in thefollowing drawings, the

same being merely a preferred exemplary form of embodiment of myinvention, throughout which drawings like reference numerals indicatelike parts:

Figure 1 is a view in side elevation of a device embodying my invention;

Fig. 2 is a front view of the same;

Fig. 3 is a side view in elevation of said device in operative positionfor unloading the lumber;

Fig. 4 is a plan view of the driving mechamsm;

Fig. 5 is a view of the lever and tripper mechanism to control thetilting operation;

Fig. 6 is a view in section on broken line 6, 6, and

Fig. 7 is a view of the lever andtripper mechanism to control theadvance and retraction of the discharging member.

A tilting platform 8 formed of girders 9 and 10 secured together bycross beams 11 and 12, is pivotally mounted at 13. On beams 11 are tracksections 14 to receive the lumber trucks or dollies 15. Upon girder 10is mounted the discharging member 16 of triangular form disposed to moveagainst the lumber stacked on the trucks and push the load up theincline so that it will fall off the ends of the bunks 17. Thisdischarging frame (for detail see Fig. 6) has channel girders 18 on eachside slidably mounted on straps 19 secured to the beams 10. Clamps 20extend over a flange of the channel girder 18 and holds said channelupon the straps 19. A rack 21, secured to the inner side of the channelgirder 18, ex-

tends below the bottom of said channel so ing mechanism 23, consistingof a right angle clamping arm 24 mounted in a sleeve 25, said arm beingdisposed to be actuated by means of a ratchet 26 which has the handle27. By means of these elements, the arm 24 may be clampedtight againstthe stacked lumber 28 so that the bolsters 29 may be removed. A hingedapron 30 guides the falling boards to the sorting table 31.

A motor 32 has a shaft 33 which has a worm 34 disposed to engage theworm gear 35 mounted 011 shaft 36, upon which are idlingly mounted thebevel gears 37 and 38, the same being subject to engagement with theclutch members 39. Also, mounted upon shaft 36 are the sprocket wheel 40(idlingly mounted) and the pinion 41 which are engageable by the clutchmembers 42. From this general driving base the following engagements aremade:

5 (1) To tiltfithe platform, bevel gear 43 is mounted in engagement withthe bevel gears 37 and 38. Bevel gear 43 is mounted on shaft 44, whichhas worm 45 (shown in dotted line under worm wheel 46) disposed toengage worm gear 46 on shaft 47, and said shaft in turn having pinion 48engageable with the tilting rack 49 mounted on tilting platform 8.

(2) To drive forward and retract the discharging frame (see Figs. 4 and6), pinion 41 engages large gear 50, which is mounted on a shaft 51,which, also, has keyed thereto gear 52 and sprocket wheel 53. Gear 52 ispositioned so as to engage gear 54 carried by the tilting platform 8when said platform is tilted to a predetermined angle. Gear 54 ismounted on shaft 55, which has right and left handed worms 56 and 57respectively. These worms in turn are engageable respectively with thehorizontally mounted gears" 58 and 59 mounted on shafts 60 and 61 on theoppositeend of which shafts are gears 62 and 63, which engage the rack21 carried by the channel 18 of the discharging member 16. Shaft 55 hasbevel gear 64 engageable with gear 65 on shaft 66, whereby a wrench 67can be applied to one end 68 of shaft 66 when it is desired to manuallyadvance or retract the discharging member 16. The chain 69 connects thetwo sprocket wheels 40 and 53. v

(3) To automatically stop the tilting of the tilting platform 16, atripper control may be provided to throw the clutch 39 into neutralposition, said tripper comprising pivotally mounted arm 70 engageablewith the clutch members 39, an arm 71 pivotally connected at one end tosaid arm 70 and pivotally connected at the other end to the angularlyformed and pivotally mounted tripper 72, which tripper is dis posed tobe operated by the extension member 73 which may be secured to the sideof the girder 9 as it moves up or down, said end bearing as it descendsagainst the incline 74 and as it ascends against the incline 75 of thetripper. Clearly, the tripper 72 may also be manually moved out or in,depending on position of the platform 8.

(4) The clutch members 42 may be controlled by the lever 76 (see Fig. '7for detail) and its connecting members 77, 78, 79, 80 and 81.

The mode of operation of a device embodying my invention will next beset forth. The sequence of operations may be varied and in general theymay be as follows:

A load of stacked lumber 28 is run upon the track sections 14. Thewrench 67 is employed to advance the discharging frame 16 against theload 28 of lumber, clutch members 42 being in neutral position. Theratchet 26 through handle 27 is then operated to draw clamping arm 24into firm position against the lumber on the front ide; e, the d e these ene t b so t t he b ls ers 2 n a d-fro t sid ybe n xt rem d fife hebunk i T e tripper 7 f 'the ree to move clntcl'- 1 men1bers 39 so thatgear 13' is caused to be actuated: to raise tl' epla'tform 8- intotilted position as appears in Fig. 3; When gear 453 is driven, pinion 48through its conifiectijons is set in motion against the rack The weightof the end portion of the platform 8 opposite the pivoted end is carriedby the rack 49 and the. pinion 48 so that there is no play therebetween.

To advance the discharged member 16, the lever T6 is next operated tomove clutch members 42 so that the 'p'injion 41 is caused to actuate thelargegear '0, and hence gear 52 is actuated and through it gear 54:.Then e Worms .6 am. r actuated, d as these engage gears 58 and 59, gears62 and are set in 'motion against the racks '21 of the dischargingmember 16.

This discharging member 16 then pushes the lumber up the inclined bunks17 at a predetermined speed, and causes the lumber o to fall? off theend, tierby' tier, whence the lumber moves down the apron 30'to thesort;- ing table 31,, The clamping arm 2st may be loosened if necessaryto free the boards. The incline is preferably of such an angle that thestack maintains itsstacked position without any releasing or yieldingmeans pressing against the front side thereof; and the lumber is thusfree to; fall by theforce of gravity so soon as displaced from theendofthe bunks 17; This, arrangement preferably provides for a fixedpoint of discharge and the-lumber is moved to the'dislodging: point.This obviously greatly simplifies the mechanism and byp'r-oviding forthe movement of the lumber downwardly, the rate ofunloading is greatlyincreased, aswell as eliminates the difiiculties arising upon the.breaking of a tier. The spacing strips (not shown) be tween the tiers oflumber are removed in the same direction as are the'boards so that noseparate provision is required for' their disposal. p

lVhen the load of lumber 28 is discharged, clutch members 12 arethenmoved into neutral position so that the advance of the dischargingmember 16 is stopped. This may be done automatically by having anextension member 82 carried by the discharging member 16 engage thelever 76. The clutch members 12 are manually moved by lever 76 totransmit power to the sprocket wheel 40 and thence to sprocket 53 whichrapidly retracts the discharging member 16. Obviously, the completecycle of movements can be rendered automatic by making use of trippingdevices well known in the art.

Obviously, changes may be made in the forms, dimensions and arrangementsof the parts of my invention without departing from the principlethereof, the abOVeQsetting' forth only a preferredformof embodiment Iclaim:

1. An unloading mechanism embodying a tiltingplatfo-rm, one end of whichis dis posed to receive material to be unloadedin predetermined order,one vertically CllS- posed section after another; and a discharg ingmember slidab'ly mounted on said platform disposed to maintain saidmaterial in vertically disposed sections when said platform istil-L edand to move lengthwise of said platform, whereby said material is pushedupwardly relative the inclined platform and edits and in saidpredetermined order.

2. An unloading mechanism embodying a tilting platform, one end of whichis disposed to receive material to be unloaded in a predetermined order,one vertically disposed section after another; a clamping means;disposed to hold said material in position; and a discharging memberslidably mounted on said latform disposed to maintain said material invertically disposed sections when said platform is tilted and to movelengthwise of said platform, whereby said material is pushed upwardlyrelative the inclined platform and off its end in said predeterminedorder;

3', An unloading mechanism embodying a tilting platform, one end ofwhich is dis posed to receive material to be unloaded in apredetermined. order; one vertically disposed sect-ion after another;means to cause said platform to tilt; and a discharging memberslidablymounted on said' platform disposed to maintain said material invertically disposed sections when said platform is tilted and to movelengthwise of said platform, whereby said material is pushed upwardlyrelative the inclined platform and off its end in said predeterminedorder.

4; An unloading mechanism embodying a tilting platform, one end of whichis disposed to receive material to. be unloaded in a predeterminedorder, one vertically disposed section after another; means to causesaid platform to tilt; a clamping means disposed to hold said materialin position; and a discharging member slidably mounted on said platformdisposed to maintain said" material in vertically disposed sections whensaid platform is tilted and to move lengthwise of said platform, wherebysaid material is pushed upwardly relative the inclined platform and offits end in said predetermined order.

5. An unloading mechanism embodying a tilting platform; track sectionson said platform; trucks carrying materials to be unloaded disposed onsaid sections; and a dis charging member disposed to move crosswise ofsaid truck, whereby the position of the material on said truck ischanged.

Fri.

6. An unloading mechanism embodying a tilting platform; track sectionson said platform, the pivoting point or axis of rotation of saidplatform being positioned intermediate said tracks; trucks carryingmaterials to be unloaded disposed 011 said sections; and a dischargingmember disposed to move crosswise of said truck, whereby the position ofthe material onsaid truck is changed.

7. An unloading mechanism embodying a tilting platform; means wherebysaid platform is actuated into tilting position; track sections on saidplatform; trucks carrying materials to'be unloaded disposed on saidsections; and a discharging member disposed to move crosswise of saidtruck, whereby the position of -the material on said truck is changed. pl

8. An unloading mechanism embodying. a tilting platform; track sectionson said platform; trucks carrying material to be unloaded disposed onsaid sections; a discharging member disposed to move crosswise of saidtruck, whereby the position of thematerial on said truckv is changed;means whereby said platform may be actuated into said tilting position;and a clamping means disposed to hold said material in position.

9. In combination with an unloading mechanism, a discharging memberdisposed to support the material units to be unloaded in a predeterminedposition and'to move said units to the point of discharge.

10. In combination with a lumber unloading mechanism having a tiltingplat-form, a discharging memberdisposed to changethe position of thelumber to be unloaded, said discharging member embodying an uprightframe, and driving means to cause said frame to move against the lumberto be unloaded, whereby the said lumber may be unloaded in apredetermined, orderly manner.

11.. In combination with a lumber un-' loading mechanism having atilting platform, a dischargmg member disposed to change the position ofthe lumber to be unloaded, said discharging member embodybe unloaded in'a predetermined, orderly manner.

12. In combination with a lumber unloading mechanism having a tiltingplatform, a discharging member disposed to change the position of thelumber to be unloaded, said discharging member embodying an uprightframe, means to move said frame preliminarily into position against saidlumber, and driving means to cause said frame to move against the lumberto be unloaded, whereby the said lumber may be unloaded in apredetermined,:orderly manner.

13. In combination with a lumber unloading mechanism having a tiltingplatform, a discharging member disposed to change the position of thelumber to be unloaded,said discharging member embodying anupright frame,means to move said frame preliminarily into position against saidlumber, driving means to cause said frame tomove against the lumber tobeunloaded, and a control member to automatically cause the advance ofsaid frame to be stopped, whereby the said lumbermay be unloaded in apredetermined, orderly manner.

14. An unloading mechanism embodying a tilting platform; a carriage onwhich ma terial to be unloaded may be disposed;.&

sup-porting means on said platform to receive said carriage; a clampingmeans mounted on said platform independent of said carriage; and adischargingmember disposed to move against said material.

15. A lumber unloading mechanism embodying a tilting platform,supporting means on said platform to receive lumber stacked in tiers tobe unloaded, a clamping means disposed to hold said lumber in positionduringthe tilting operation, means to adjustably release said clampingmeans preliminary to the unloading operation, and a discharging memberdisposed to move against said lumber, displacing said lumber crosswiseofsaid supporting means, whereby said lumber may be caused to beunloaded board by board and tier by tier, said boards descending underthe force of gravity.

my name this 18th day of May, 1921.

JAMES I., POLLOGK.

In witness whereof, I hereunto subscribe

